#静态方法  封装my-math
class MyMath:
    @staticmethod
    def add(a, b):
        return a + b
    @staticmethod
    def sub(a, b):
        return a - b
    @staticmethod
    def mul(a, b):
        return a * b
    @staticmethod
    def div(a, b):
        return a / b
    @staticmethod
    def ediv(a, b):
        return a // b
    @staticmethod
    def rem(a, b):
        return a % b
    @staticmethod
    def sqrt(a):
        return a**(1/2)

#为自定义类添加功能
class caixi :
    delicious_caixi = True          #添加类属性
    __jiachangcai = "家常菜"         #添加私有属性

    def __init__(self, name):

            self.name = "汉堡"    # 初始化实例属性
            self.__name  = name          # 绑定私有实例属性

    @classmethod
    def __new__(cls,*args, **kwargs):
        print("好吃")
        return super().__new__(cls)
